Learning Objectives: Neuropathology of Traumatic Brain ... · • King-Devick Test ... The maximum...
Transcript of Learning Objectives: Neuropathology of Traumatic Brain ... · • King-Devick Test ... The maximum...
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The Optometrist’s Role in TBI Prevention and Treatment
May 8, 2017
Jennifer Simonson OD, FCOVD Boulder Valley Vision Therapy
1790 30th Street, Suite 311Boulder, CO 80301
Learning Objectives:• To understand the impact of Traumatic Brain Injury
(TBI) on patients’ neurological and visual performance
• To diagnose post-concussive vision syndrome
• To gain insights in how to best treat visual deficits related to TBI
Neuropathology of Traumatic Brain Injury
(TBI)
Incidence of Traumatic Brain Injury (TBI)• TBI incidence in the US:
1.7 million (CDC) to 4 million (Journal of Neurology) PER YEAR
http://www.traumaticbraininjury.com/understanding-tbi/what-are-the-causes-of-tbi/
ER and Hospital Stats
Males >> Females
Most at risk: ages 0-4, 15-19, >65 years
Highest rate of TBI-related ER visits,
hospitalizations, and deaths is Males 0-4
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TBI in Sports• High school football accounts for 47% of all
reported sports concussions.
• 33% of concussions occur during practice.
• Ice hockey and soccer are shortly behind football on TBI incidence.
• 1 in 5 high school athletes will sustain a sports concussion during the season.
References: www.cdc.gov/TraumaticBrainInjury
TBI in Sports
• 33% of high school athletes who have a sports concussion report two or more in the same year.
• 90% of most diagnosed concussions do not involve a loss of consciousness.
http://www.headcasecompany.com/concussion_info/stats_on_concussions_sports
TBI in Sports• 39% increase in risk for catastrophic head
injury leading to permanent neurologic disability in subsequent concussions.
• An estimated 5.3 million Americans live with a traumatic brain injury-related disability (CDC)
Neurology of the Visual Pathways in the Brain
Far reaching consequences of TBI • Visual processing occurs in
35 different areas of the brain.
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Vision is a SENSORY and MOTOR system.
• What is it?• Where is it?• What do I name it?• How do I interact with it?
Sensory – Visual Processing
• Pupil reflex• Tracking• Vergence• Focusing
Motor – Muscles in and around the eye
Effects of TBIon the visual system
• Areas of potential injury:
Types of TBIs• Acceleration - head is struck by more rapidly
moving object, ‘coup’ lesion, damage occurs at the site of impact
• Deceleration - diffuse axonal injury, contrecoup effect, brain moves in the skull, axonal injury occurs at the site and opposite site of impact
• Left Hemisphere injury - motor weakness on the right side; Aphasia
• Right Hemisphere injury - motor weakness on the left side; visual attention and spatial orientation deficits
Examples:https://www.youtube.com/watch?v=tdRYVZtiKg8
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Post-traumatic Vision Syndrome
Visual Deficits
Following TBI
• Accommodative Insufficiency
• Oculomotor Dysfunction
• Convergence Insufficiency/Binocular
Instability
• Visual-Vestibular Disequilibrium
• Impaired Visual Processing
• Visual Field Loss
• Dry Eyes
• Light Sensitivity
Most commonly reported symptoms (Lovell et all 2004)
Symptoms Percent
#1 Headache 71 #2 Feeling slowed down 58#3 Difficulty concentrating 57#4 Dizziness 55#5 Fogginess 53#6 Fatigue 50#7 Visual blurriness/double vision 49#8 Light sensitivity 47#9 Memory dysfunction 43#10 Balance problems 43
Ocular Motor Dysfunction following mTBI Capo’-Aponte et. Al Military Medicine 2012
Type of visual Impairment %mTBI %controls p
Convergence Insufficiency 55% 5% 0.0012
Saccadic Impairment 30% 0% 0.0202
Pursuit Impairment 60% 0% 0.0001
Ocular Misalignments (vertical phoria) 55% 5% 0.0012
Ocular Misalignments (horizontal phoria) 45% 5% 0.0084
Accommodative Dysfunction 65% 15% 0.0031
After neurological incident• Stationary objects appear to move• Seeing words and print run together• Intermittent blurring• Having significant difficulties in crowded moving
environments• Are told that their eyes are healthy and that this is
not in their eyes• Anxiety is heightened• Approximately 90% of people with TBI have visual
problems.
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Visual Symptoms after TBI Diagnosis of TBI-related Visual Deficits
Post-traumatic vision syndrome
definition• Dr. William Padula: Insult to the cortex causes stress in the
central and autonomic nervous system. It is postulated the disruption occurs at the level of the midbrain, vision is matched with kinesthetic, proprioceptive, and vestibular processes.
• Affects peripheral fusion, pre-planning, and spatial organization
Post-traumatic vision syndromeCharacteristics:
photophobia reduced concentration Inattention objects appear to move balance and coordination issuesmotion sickness difficulty working under fluorescent lights visual-perceptual motor dysfunction
Visual Field Deficits
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Cranial Nerve 2: Optic Nerve
• SENSORY
Cranial Nerve 3: Oculomotor Nerve
• MOTORo Medial Rectuso Superior Rectuso Inferior Rectuso Inferior Obliqueo Upper eye lidso Pupil constrictiono Focusing of lens via Ciliary
Body Muscle
• MOTOR
Cranial Nerve 4: Trochlear Nerve
Cranial Nerve 6: Abducens Nerve
• MOTOR
http://www.eyedock.com/parks-3-step
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Post-traumatic Vision Examination
OCULAR MANIFESTATIONS OF NEUROLOGICAL INSULT
Headaches with visual tasks
Blurred vision
Double Vision
Loss of Depth Perception
Loss of Visual Field
Aching eyes
Visual Overload
Poor Attention/Concentration
Reading difficulties
Case HistoryKey questions to ask post-injury (Goodrich et al, 2013)
1. What changes have you experienced in your vision? 2. Are you light sensitive, in- or outdoors? 3. Do you experience double vision? 4. Have you noticed a change in your peripheral vision?5. Do you have blurred vision at distance or near? 6. Has there been a change in reading? 7. Do you lose place while reading? 8. How long can you read before you need to take and break or
stop? 9. Do you experience Headaches?10.Do you have trouble remembering what you’ve read?
Detailed Questionnaire: 0-3 ScaleEmergent Visual Conditions• Flashes of light• Floaters in field of view• Restricted field of vision• "Curtains" billowing into field of view
Urgent Visual Conditions• Inability to completely close eyes• Difficulty moving or turning eyes• Pain with movement of the eyes• Pain in or around eyes• Wandering eye• Double vision
Dr. Allen Cohen at SUNY
Detailed Questionnaire: 0-3 Scale• General fatigue while
work/reading• Loss of place while reading• Eyes get tired while reading• Headaches while reading• Covering, closing one eye• Easily distracted when reading• Decreased attention span• Reduced concentration ability• Difficulty remembering what
has been read
Vision Rehabilitation Conditions• Blurred vision for distance
viewing• Blurred vision for near viewing• Slow shift of focus from near
to far to near• Difficulty copying or taking
notes• Pulling or tugging sensation
around eyes• Discomfort while reading• Unable to sustain near work or
reading for periods of time
Dr. Allen Cohen at SUNY
Detailed Questionnaire: 0-3 Scale Disorientation Loss of balance Poor posture Face, head turn or head tilt Bothered by movement in environment Bothered by crowded environments Light sensitivity A sensation of the floor, ceiling or walls tilting Dizziness A sensation of the room spinning A sensation of not feeling grounded Postural shifts/ veering off when walking
Dr. Allen Cohen at SUNY
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What is tested during an eye examination?
1. Visual Acuity2. Refractive Status3. Oculo-motility4. Accommodation5. Binocularity6. Visual fields/peripheral vision7. Color Vision8. Pupils9. Eye Health
• Eye structure• CN II, III, IV, VI• Parasympathetic/Sympathetic Nervous System
Optometric testing -Oculomotility
• Assess range, nystagmus, fatigue• Pursuits• Saccades • Developmental Eye Movement Test• King-Devick Test
https://www.oepf.org/sites/default/files/journals/jbo-volume-3-issue-6/3-6%20Maples.pdf
VOMS• https://www.youtube.com/watch?v=CJF6kJcFGqE
Visual Oculo-motor Screening
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Optometric testing -Accommodation
• Nearpoint of Accommodation• MEM Retinoscopy• Fused Cross Cylinder• Amplitude (minus lens or pull away
method)• NRA - PRA• Facility (+/-2.00 or less depending on age)
Optometric testing -Binocular Vision
• Alignment - Cover testing, Maddox rod, Worth 4 dot, Modified Thorington
• Near Point of Convergence • Stereopsis: Randot, Stereo Fly• Vergences• Risley prism or prism bar - distance and near • Prism facility (8^BI/BO)
Pupil Testing
Symptoms• Eyestrain• Visual fatigue• Squinting• Headaches • Eye pain• Intolerance to lights• Alpha/omega
pupil(Parasympathetic/sympathetic imbalance)
• Retained Primitive reflexes(Moro)
Causes• Dry eye, corneal surface • Blink rate• Pupil size/reaction• Uncorrected refractive
error• Inflammation• Receded NPC, poor fusion• Cataracts• Optic nerve problems• Macular trauma• Visual field defect
Light Sensitivity Visual deficitsVisual field loss
Total loss - optic nerveHomonymous defects Bitemporal - optic chiasm,
Non-congruous - optic tract, LGN
Hemianopsia - optic radiationsQuadrantanopia - Temporal lobe,
optic radiations
Spatial inattentionAlso called Unilateral Spatial
NeglectInability to attend to meaningful sensory stimuli presented in the
affected hemi-fieldRight parietal lobe lesion, injury, or
stroke of the middle cerebral artery
Competitive process with difficulty perceiving certain stimuli
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Visual spatial inattention• “Neglect”
http://slideplayer.com/slide/5279716/
Dr. Carl Garbus
• The Star Cancellation Test: In the Star Cancellation Test, the stimuli are 52 large stars, 13 letters, and 10 short words interspersed with 56 smaller stars. The patient must cross out with a pencil all the small stars on an 8.5″ x 11″ piece of paper. Two small stars in the center are used for demonstration. The page is placed at the patient’s midline.
• https://www.strokengine.ca/indepth/sct_indepth/
Visual spatial inattention
Visual spatial inattention• Scoring:
The maximum score that can be achieved on the test is 54 points (56 small stars in total minus the 2 used for demonstration).
• A cutoff of < 44 indicates the presence of USN. A Laterality Index or Star Ratio can be calculated from the ratio of stars cancelled on the left of the page to the total number of stars cancelled. Scores between 0 and 0.46 indicate USN in the left hemispace. Scores between 0.54 and 1 indicate USN in the right hemispace.
• https://www.strokengine.ca/pdf/starcancellation.pdf
Clock Drawing Test• Free drawn clock: the individual is given a blank sheet of paper and
asked first to draw the face of a clock, place the numbers on the clock, and then draw the hands to indicate a given time. To successfully complete this task, the patient must first draw the contour of the clock, then place the numbers 1 through 12 inside, and finally indicate the correct time by drawing in the hands of theclock.
Visual disorders may not be fully expressed or understood by
the patient.
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Ambient / Magnocellular System
• “Where is it?” / Big picture Focal / Parvocellular System
• “What is it?” / Details
VISION: A TALE OF TWO SYSTEMS
EGOCENTRIC LOCALIZATION ASSESSMENT Images courtesy of William Padula’s paper: Post Trauma Vision Syndrome & Visual Midline Shift Syndrome. Neurorehabilitation 6 (1996) 165-171
EGOCENTRIC LOCALIZATION ASSESSMENT EGOCENTRIC LOCALIZATION (AKA: MIDLINE SHIFT)
• Symptoms: • Falling over or losing balance
• “Straight lines aren’t straight.”
• “It looks like things are moving.”
• Assessment: • Check vertical and horizontal planes
• Balance / Posture assessment • Walking
• On a compliant surface
• Where is the patient’s center of balance?
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TBI Prevention, Education and Outreach
Outreach• Awareness• Risk Assessment
• Athletes• Coaches• Athletic Trainers• Parents• Recreational activity
participants• Rehabilitation
professionals: PT/OT
Concussion PreventionScreening Tests: King-Devick (K-D) Test
1. Accurate diagnostic test for identifying concussion
2. For use at the sideline and in the office
Vision ScreeningsSports Training
Pre-season Training ProtocolsGains made in: 1. Stereopsis2. Athletic performance3. Significant reduction in concussions for the
season
Concussion Evaluation:• Recommend Vision Evaluation 1 month following TBI• Post-concussion syndrome occurs when symptoms of
TBI persist following 1-3 months post-injury
Optometric Treatment and Vision Rehabilitation
Optometric Treatments for TBI PatientsSpectacle prescription –
• Small refractive errors often make a large difference. Note even small amounts of plus, minus, astigmatism or prism
• Tinted Lenses - indoor and outdoor useo Blueo Grayo Browno Rose
(FL-41 anti-migraine)
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Lenses• When treating diplopia
consider: a) Low plus for near workb) Prism - compensating
or yoked, Fresnel or ground-in
c) Bi-nasal Occlusiond) Single vision/Standard
bifocals vs. PAL designse) Partial or Spot
Occlusion - can alleviate double vision
Prism• Field Loss
o Prism to increase field awareness
• Yoked prism for shifting body midline
http://slideplayer.com/slide/10233419/Dr. Saeed
Optometric Treatments for TBI Patients• Environmental and wellness recommendations
o Lighting – eliminate fluorescent lightingo Computer Screens
• Reduction in screen time and near work often necessary• Changing the color spectrum• Adjusting brightness
o F.luxo Phone settings
Vision Rehabilitation1. Vision therapy designed
for patient’s diagnosis and goals
2. Visual-vestibular therapy often required
3. Specialized therapy for visual inattention and other visual processing deficits
Vision Therapy is Sensory Integration Therapy
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Vision Therapy is Neuro-Muscular
TherapyVision
Therapy is Perceptual Therapy
Concussion
Ocular
Vestibular
Cognitive/ Fatigue
Post-Traumatic
Migraine
Cervical
Anxiety/Mood
DeAnn M. Fitzgerald, ODDr. Fitzgerald and AssociatesCedar Rapids, Iowa
General health considerations
• Nutrition• Exercise• Multidisciplinary, team approach
o Patients may be seeing multiple practitioners
Referral recommendations: Chiropractor, Occupational Therapy (OT), Physical Therapy (PT), Speech Therapy (ST), Psychologist, Cognitive rehabilitation, Physiatry, Acupuncture, Cranio-sacral therapy, Revive Center
Take Away Points:• You will see patients with a history of TBI.• These patients will have visual symptoms in most cases.• You will help identify injury to the eye and neural
pathways in the brain.• You can tremendously help the function of these
patients with lenses, prism, selective occlusion and tints.• You can help relieve visual symptoms of eye strain,
headaches, and dry eye syndrome.• You can help these patients connect with a
rehabilitation team which may include referral to low vision specialists or vision therapy.
References1. Website (retrieved 2/7/2017)
http://casemed.case.edu/clerkships/neurology/NeurLrngObjectives/Vision.htm
2. Review of Optometry, “Save a Life, Neuro-Optometry Primer: The Brain” by Mario Gutierrez, OD, FAAO. https://www.reviewofoptometry.com/CMSDocuments/2009/9/Neuro-Optom-Supp_RO-09.02.09.pdf
3. http://cpdailyliving.com/cortical-visual-impairment-cvi-cerebral-palsy-underdiagnosed-undertreated/
4. http://www.perkinselearning.org/videos/webcast/cortical-visual-impairment-and-evaluation-functional-vision
5. http://www.visiontherapysuccess.com/headtrauma.php